Hallway Lighting Project: Installing the NeoPixel Strips

In which we start to learn about Adafruit's NeoPixels and Steve's use of them in the skirting board of his hallway.

In my previous column, I explained how I've had a thing for flashing lights as far back as my early teens. Anything from a flashing LED to a full-blown laser show can have me transfixed.

I also discussed the various projects I've built over the past 30-plus years. Looking back, it's amazing how dated the technologies I used to use have become. These days, we have all sorts of amazingly powerful, yet affordable, technologies available to us, such as Arduino microcontroller development platforms and NeoPixel strips from Adafruit.

Until a few months ago, I'd only messed around with the NeoPixels, just showing them off to my friends, family, and work colleagues. I did wrap 10 meters of them around my Christmas tree this Christmas past, and I also attached a few to a Christmas hat for the missus (I used a Trinket for the hat and an Uno for the tree).

After Christmas, I decided that I needed to do something more meaningful with these pixels, especially as I had so many of them. For years, our hallway had been illuminated by a set of old blue LED Christmas lights wrapped around a bunch of dried painted sticks stuck in a pot. Although this may not sound like much, it provided a nice ambient light and we seldom used the main lights. The missus and I recently decided to redecorate the hallway and stairs. We decided to paint everything white and lay a nice laminate floor in the hallway. As part of this effort, I removed the existing skirting boards as I wanted to replace them with taller ones.

With everything white, the hall and stairs did look a little minimalist. That's when I thought I could use the Neo-pixels to add some colour. We decided the new skirting boards would be a good place to mount the LEDs, but how was I to get power to them and control them? Luckily, the hallway cupboard has a power outlet. All I had to do was mount an AC-to-DC power supply in the cupboard and some sort of controller in the wall somewhere in the hallway close to the power supply. The Missus said she was up for this, so my project started soon after.

I must admit to being somewhat concerned that the end result might look a little garish. This wasn't helped when I discussed the project with others and they responded with things like: "Why on Earth do you want to do that?" Regardless, my mind was made up. Now that the project is complete, I have to say it looks great, and these lights are used every day to either display a static colour to or slowly fade from one colour to another -- Adafruit's rainbow effect makes an occasional appearance also as seen in a video I posted to YouTube. I do intend to add a party mode with more active and faster patterns, but that is still to come.

Mounting the NeoPixel strips in the skirting board
The skirting board requires a recess to accommodate the NeoPixel strips, along with a wider recess to hold the diffuser. Two 5-meter reels of pixels were stripped of their waterproof sheath so that measurements could be taken. After practicing on some skirting board off-cuts, I decided to route two recesses along each skirting section using the same centreline. The first recess was 11mm wide by 5mm deep (2mm for the depth of the pixels plus 3mm for the opal acrylic diffuser), while the second recess was 16mm wide by 3mm deep.

The Arduino is an reasonably priced open source device with a tone of support. They are relatively easy to program using the dedicated and free Integrated Development Environment and can be used on a PC, Mac or Linux.

@Sheetal: Every year we use LED lights bought from the shop, it will be great to build something on your own and then you can keep getting better year after year. How do we get started?

The NeoPixels strips from Adafruit that Steve is using are great -- you buy them by the meter and they come in a waterproof plastic sleve so you can use them outside. You can get them with 30, 60, or 144 pixels per meter -- I'd probably stick with the 30 pixels per meter for what you are doing.

The really great thing is that you can control multiple meeters using a single pin on an Arduino -- and you can have multiple strips each using its own pin.

@Sanjib: Hope Cybil was not in playful mood while you were fixing those panels & wires...

My wife has two cats -- Coco (a.k.a. Coconut) nut and Drummer (a.k.a. Harrogate) -- as soon as I get my soldering iron out and layout my components and wires and suchlike, they both bounce up on the table to see what's going on -- grrrrr

@Steve, Yes in India we have very big festival of lights around October and every household is decorated with lights. Every year we use LED lights bought from the shop, it will be great to build something on your own and then you can keep getting better year after year. How do we get started?